Known types of slide door apparatus are disclosed in Japanese Patent Laid-Open Publication Nos. Hei. 9-4323, Hei. 10-8828, and Hei. 10-18708.
In each of these apparatus, when an electrically operated driving mechanism is turned on, the resultant rotation in one direction moves the slide door in its opening direction, thereby opening the opening area formed in the side of the vehicle body. The resulting rotation in the other direction moves the slide door in its closing direction, thereby closing the opening area formed in the side of the vehicle body.
A clutch mechanism is interposed between the driving mechanism and the slide door. If the clutch mechanism is in its disengaged condition, the slide door is isolated from the driving mechanism, thereby allowing the slide door to be moved manually. However, when the vehicle is parked on a sloping road, the gravity applied to the inclined slide door causes the door to be opened unexpectedly and excessively fast.
Accordingly, a need exists for a slide door apparatus for vehicles in which the sliding speed of the slide door is controllable or adjustable.